Photographic processing apparatus



Jan. 12, 1965 s. L. HERSH PHOTOGRAPHIC PROCESSING APPARATUS 5Sheets-Sheet 1 Original Filed Feb. 6, 1961 uvvnvron, SEYMOUR L. HERSHATTORNEY.

Jan. 12, 1965 s. HERSH 3,155,047-

PHOTOGRAPHIC PROCESSING APPARATUS Original Filed Feb. 6, 1961 5Sheets-Sheet 2 FIG. 2

INVENTOR, SEYMOUR L. HERSH ATTORNEY.

Jan. 12, 1965 s. HERSH PHOTOGRAPHIC PROCESSING'APPARATUS 5 Sheets-Sheet3 Original Filed Feb. 6, 1961 mdE INVENTOR, SEYMOUR L.

I WMXWERSH ATTORNEY.

Jan. 12, 1965 SJL. HERSH PHOTOGRAPHIC PROCESSING APPARATUS OriginalFiled Feb. 6, 1961 5 Sheets-Sheet 5 FIG.8

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- 1 'I l w T POWER SOURCE FIG. 9 -|2| SOLUTION IOO TEMPERATURE 9 3OCONVEYOR I DRIVE I02 7 MOTOR |o2 |o2 I02 F SUCTION. L FAN 99 99 4|/MOTOR INVENTOR, SEYMOUR L. HERSH ATTORNEY United States Patent M3,165,047 PHOTDGRAIHIC PROCESSING APPARATUS Seymour L. Hersh, Freehold,N.J., assignor to the United States of America as represented by theSecretary of the Army Original application Feb. 6, 1961, Ser. No.87,505. now Patent No. 3,104,602, dated Sept. 24, 1963. Divided and thisapplication Mar. 1, 1962, Ser. No. 176,832 9 Claims. (Cl. 95-775)(Granted under Title 35, U.S. Code (1952), sec. 266) The inventiondescribed herein may be manufactured and used by or for the Governmentfor governmental purposes without the payment of any royalty thereon.

This application is a divisional application of the application by thesame inventor bearing Serial No. 87,505, filed in the US. Patent Officeon February 6, 1961, for Photographic Processing Apparatus, now PatentNo. 3,104,602. 7

This invention relates to a machine for handling and processingphotographically sensitized elements and particularly to thesemiautomatic processing sequence including registering of an originalsuch as a processed negative upon the surface of a sensitized sheet,exposing the sheet through the negative, and processing the exposedsheet.

Machines have been used heretofore for printing and processingphotographic materials but have failed to provide the fast and efficienttechnique offered by the present invention wherein an exposing means isparticularly devised for direct integration of its function with that ofthe subsequent single or multiple step chemical processing operations.The chemical processing operations are carried out upon a compactcylindrical device wherein the exposed sensitive sheets are presentedsuccessively to processing heads which apply a film of solution to theemulsion sid of the sheet only. Thus the operation is completed withoutthe use of multiple open trays in which the sheets are completelyimmersed and withdrawn. This latter operation is wasteful of space andsolutions. Moreover when the sheets are so immersed, drying becomes awasteful power and time consuming operation.

The mechanism of the invention provides a hollow glass cylinder rotatedon its axis and having an elongated lamp therein. A guide platenfacilitates the feeding of a sheet of printing paper and a negativeregistered in contact therewith into the printing section of the devicewhere they are carried along between the periphery of the cylinder and adriven apron at the upper portion of the cylinder. While passing throughthis conveying means the sheet is printed by the light emerging from aslot in a housing surrounding the lamp.

Immediately upon emerging from this conveyor means the negative andprinting sheet separate and the sheet, continuing its movement, engagesa second conveying means having a second driven apron. The second apronmay be an extension of the first mentioned apron. This apron is porousand engages the printing sheet to move it in a cylindrical path incontact with the cylinder and while so traveling the sheet encounters aplurality of processing units of special construction to be describedhereinafter. Each unit has a small elongated outwardly open solutionchamber extending across the print. When no print is present the chamberis open and a solution circulating pump of the vacuum type runs idly.When a print covers the open chambers and seals off the vacuum leak,solution circulates in the chambers to process the print which is thenconveyed to an infra red drying station.

The complete system which will subsequently be described providesperfectly coordinated handling and timing control of the negative andprinting sheet at every instant while they are printed and during thechemical processing of the print.

3,165,047 Patented Jan. 12., 1965 It is a primary object of theinvention to provide an apparatus for uniformly feeding individualexposed cut sheets of printing material through a succession ofprocessing steps without immersing the sheets in the solutions.

A further object of the invention is to provide an apparatus for feedingexposed printing sheets through a series of processing stations in acontinuous motion and achieving optimum conditions for high qualityresults at each station.

A further object of the invention is to provide a continuously operatingapparatus wherein exposed sheets of printing material are processed byautomatically applying individual solutions for each step in the processto the emulsion side of the sheet only in a thin film while the sheetspass through the apparatus and removing the processing liquid from theapplicator when no sheet is present.

A further object of the invention is to provide an apparatus forprocessing exposed printing sheets wherein the solutions are applied tothe sheets through lateral slots in solution applying units while thesheets move thereover and wherein the presence of the sheets coveringthe slots acts to initiate fiow of solution through the slots.

A further object of the invention is to provide an ap paratus forprocessing exposed printing sheets wherein the sheets are moved throughthe apparatus by driving contact with their edges and narrow edgemargins only of their emulsion faces.

Other objects and features of the invention will more fully appear fromthe following description and will be particularly pointed out in theclaims.

To provide a better understanding of the invention it will be describedin comiection with the accompanying drawings wherein:

FIGURE 1 is a top plan view of the apparatus.

FIGURE 2 is a side elevation of the apparatus.

FIGURE 3 is a cross section on line 3-3 FIGURE 1.

FIGURE 4 is an end elevation looking from the right.

FIGURE 5 is a bottom plan view of the suction chamber of the apparatus.

FIGURE 6 is a detail perspective view of one of the chemical solutionapplying units of the apparatus.

FiGURE 7 is a detail cross sectional view through the apparatus at oneof solution applying units.

FIGURE 8 is a partially schematic perspective view of the solutionpumping system of the apparatus.

FIGURE 9 is a circuit diagram showing the power sup ply connections forthe apparatus.

The apparatus is compactly integrated and preferably its components aremounted upon a common base 10. The device executes photographicfunctions known as contact printing and chemical processing. A negativeor other transparent subject of a similar sheet like form is placed incontact with a cut sheet of printing material of a size corresponding tothe negative and both are held in register while they are fed into theleft hand end of the apparatus Where they are held together in closecontact while they are fed through an exposing station. It is alsopossible to use a continuous strip of printing material.

The elements of this station are supported by side frame plates 11 whichare in turn supported on the base 10 by brackets 12. The side plates aretied together at their top edges by a top plate 13. Between the sideplates is rotatively mounted a hollow glass cylinder 14 which issupported and driven upon its axis by a plurality of rolls and conveyoraprons associated therewith. Certain of these rolls and their associatedapron also serves as conveying means for the negative and printingpaper. A single apron serving all of the components of the apparatus maybe used. Rolls 15 and 16 are mounted in bearings in the side plates 11and are parallel to the axis of the cylinder 14. The top plate 13 isextended toward the scribed hereinafter.

right a substantial distance and its outer end is provided with a pairof brackets within which is rotatably mounted the roll 17 whose axisdesirably is parallel to roll 16 and at the same distance from the base19.

An endless belt or conveyor apron 18 travels around the rolls 15, 16 and17. The apron may be of any suitable porousfabric or perforated plasticsheet material and travels around roll 15 over the upper surface of roll16, around roll 17 and back to the cylinder 14, where it passes betweenthe cylinder and roll 16, over a portion of the surface of the cylinderand back to the roll 15. The apron is as Wide as the widest materialbeing processed.

A pair of rolls 19 and 20 over which travel a belt 21 are positioned atthe bottom portion of the cylinder in such manner that the upper run ofthe belt 21 firmly engages the cylinder. The rolls 19 and 24) aresupported in bearings received in the side plate 11 and the shaft 22 ofroll2tl is extended beyond the side plate to receive a driving worm gear23. The gear 23 is'engaged by a worm 24 which is journaled in bearingssecured in the side plate 11. A worm driving shaft 25 has a gear 26secured thereto which meshes with a gear 27 upon a shaft 28 supportedupon the base 11 and coupled to the output shaft of a speed changing box29 the input shaft of which is driven by a motor 30 secured to the base10. The rolls 19 and 20 and the belt 21 are thus driven by the motor 30.Any suitable driving means may however be utilized.

The end of the shaft 22 opposite to its driven end is also extended andhas fixed thereon a sprocket 31 which receives a sprocket chain which inturn travels over sprockets 32 and 33 secured to the extended shafts ofthe rolls 15 and 16 which are thus also driven by the motor 311.

As will appear more fully hereinafter the negative and the printingsheet are led into the point where the surface of the cylinder 14 meetsapron 18. To assist such insertion a guide platen 34x having sideflanges to engage the edges of the printing material is secured inposition to direct the material to the bite between the cylinder 14 andapron 18 and to insure the proper registering of the negative andprinting sheet.

The registered negative and printing sheet are clamped between the apron18 and the cylinder 14 and carried along with the driven cylinder to aposition substantially at the horizontal tangent point of the cylinderwhere the negative 34 separates from the sensitive sheet 35 at whichtime the printing sheet is fed to the bottom surface 36 of an upwardlyacting suction platen 37 which holds it in position in contact with theperforated apron while it is carried to the chemical processing stationto be de- The suction platen 37 is shown in FIGS. 3 and and consists ofa suction chamber 38 secured to the top plate 13 and positioned betweenthe top and bottom runs of the apron 18 with its bottom face 36 incontact with the bottom run thereof. The face 36 etxends completelyacross the apron and covers a substantial portion thereof along itslength. The suction chamber is provided with a suction conduit 39 whichis connected to the suction port of a centrifugal blower 40 driven inany suitable manner such as by the motor 41.

The bottom surface 36 of the suction chamber is provided with aplurality of slots 42 extending in the direction of travel of the apron18 which itself is made of porous material or it may be made of thinplastic sheet material perforated with small openings arranged to allowfree passage of air through the slots and the perforations. Thus when apartial vacuum is created in the chamber 38 atmospheric pressure willact to hold the printing sheet against the apron 18 as it is fed to theprocessing station. The length of the vacuum chamber desirably should besufiicient to support substantially the full length of the longest sheetof material to be processed or at least it should prolong the travel ofthe sheet suificiently to permit the negative 34 to emerge from betweenthe cylinder 14 and the apron 18 and fall by gravity into a container 43directly below the vacuum chamber.

The vacuum chamber hasedge guides 44 and slotted guides 4-5 foraccurately aligning the printing sheet. The slotted guides completelyembrace the edges of sheet and precisely guide the forward edge thereofinto the conveyor means on the chemical processing station. A deflectinglip 46 may be placed in the path of the sheet to finally properlyposition its leading edge.

A cylinder 47 within and concentric to the glass cylinder 14 constitutesa lamp housing having a reflector made of sheet metal supported in fixedposition upon the common axis. Any suitable means may be used to supportthis lamp housing.

Near the outer ends of the housing 47 are secured supporting strips 50upon which are mounted lamp sockets 51 within Which are received afluorescent lamp 52 or other suitable light source extending lengthwiseof the cylinder 14. Suitable electrical connections 53 supply power forthe lamp. The inner surfaces of the housing are polished and all othersurfaces thereof desirably are finished in optical black. Exposure ofthe print is made through a narrow slot 54 extending lengthwise of thehousing and at least as long as the lateral dimension of the printingmaterial. Desirably means should be provided to vary the width of theslot 54 to adjust the quantity of light flux reaching the print. Thismay be done by providing a plurality of interchangeable plates such asthe plate 55' within which the slot is cut. The plates are screwed tothe upper portion of the housing 47. The casing has an aperture thereinslightly larger than the largest slot provided by the plates 55 to thuspermit light from the lamp to reach the printing sheet 35. Desirably thehousing 4-7 has an opening 56 which is normally closed by a cover 57.This opening provides for servicing the parts inside the housingincluding replacement of lamps and the like.

If desired an additional guide roller 63 may be provided to engage thebottom face of the printing sheet 35 at the point where it emerges fromthe slotted guides 45 and just before it enters the chemical processingstation. This roll desirably consists of a plurality of discsdistributed across the width of the sheet 35 and is rotatably supportedin a frame 64 which is connected at its ends to upwardly acting springs65 which apply light pressure to the sheet by contact of the discstherewith. The frame 64 is guided in suitable slots in the brackets inwhich the roll 17 is mounted.

The exposed cut sheet of material 35 is fed to and through theprocessing station which supports, guides and transports, the sheet.Most of the components of this station are supported upon side frames inthe form of circular discs 66 and 67 of metal such as aluminum ofsubstantial thickness which are supported by brackets 68 secured to thebase 143 in parallel relation and a distance apart substantially equalto the Width of the processed sheets.

Upon the periphery of each of the discs 66 and 67 are secured ballbearings 69 upon the outer movable member of which is received a tire71) of resilient material such as rubber or plastic having an upstandingflange 71. The tires are so dimensioned that the flanges 71 are spaced adistance apart to freely receive and accurately guide the printing sheetand with the aid of the apron or belt 72 cause the sheet to be conveyedthrough the processing station, and thence to the dryer to be described.

The apron 72 is guided and driven in its travel by a series of rolls. Itis made of perforated plastic sheeting or porous fabric and issubstantially the same width as the printing sheet. The apron passesaround a roll 73 which rotates counter clockwise and is positioned tocause the apron 72 to engage the periphery of the tires 70 from Where itcontinues clockwise around the discs 66 and 67 and thence at the bottomof the discs the apron extends horizontally to the left where it engagesthe roll 74 suitably supported upon the base 10. The apron then travelsback toward the right passing over roll 75 pivoted in supports fastenedto the base and rising substantially vertically to and over-the rolls 76and 77 and back to the roll 73. An additional roll 78 may be inserted atthe bottom of the discs to provide better support for the apron as itleaves the discs.

It will be seen that the apparatus thus far described provides acomplete conveyor system for the negative and printing sheet during theprocessing cycle. The apron 72 as it leaves the bottom portion of thechemical processing station carries the finished, but slightly dampprint to a drying device 79 to be described thence, to a receptacle 80adjacent to the roll 74.

The rolls 73 and 77 are rotatively supported in a pair of brackets 81secured to the side of discs 66 and 67 while the roll 76 is mounted inbrackets 82 secured to the discs.

Suitable means is provided for driving the apron 72. As shown the shaftupon which the roll 75 pivots is extended and has fixed thereto asprocket 83 over which a chain 84 passes. This chain in turn is drivenby a sprocket 85 fixed to a shaft 86 rotatably supported in bracketssecured to the base 10. The shaft 86 also has a worm gear 87 fixedthereon meshing with a worm 88 secured to the output shaft of speedchanging unit 89 the input shaft of which is gear driven by the motor 30the shaft of which is double ended. The change speed unit is suppliedwith means for changing its driving ratio and thus varying the speed ofthe apron 72.

Along the upper periphery of the chemical processing station are secureda plurality of processing units 91), angularly spaced at a distancefound to be most effective. These processing units may be arranged toperform a variety of processing operations. In the example illustratedthe units are arranged to successively develop, short stop, fix and washthe print. One of the processing units is shown in detail in FIG. 7.They may be made of any suitable corrosion resistant material such asTeflon or metal which is non-corrosive.

The units 99 are secured between the side plates 66 and 67 in anysuitable manner as by screws engaging their end faces. The units areprovided with slots 91 which extend laterally across the path of theapron 72 and which constitute solution chambers of small liquid capacitywhich function to apply processing solutions to the emulsion of theprinting sheet. The slots are positioned to present their open sidetangential to the curve of the apron 72. As printing sheets are conveyedthrough the processing station by the apron they are caused to passsuccessively over the slots 91 and in doing so close the open sidethereof. Each slot or chamber 91 is provided with ports 92 and 93cornmunicating with opposite ends of the slots. The ports are connectedwith a system, to be described hereinafter, for applying a constant flowof processing solution to the slots. The slots are relatively narrow andshallow and thus provide for rapid change of solution. Desirably a thinend wall is provided at each end of the slots 91. Fresh solution is thusconstantly reaching the emulsion of the printing sheet as it passesthereover.

As shown in the drawings the body of the individual units 90 aresubstantially cylindrical. They may however be of any suitableconformation. It is also within the scope of the invention to provide aunitary member of Teflon or other non-corrosive material having slotstherein for all of the processing steps. However the use of individualprocessing units permits adjustment of their position along the path oftravel of the printing sheets whereby the timing of the processing stepsmay be varied. Such adjustments may be provided by forming circularslots 94 in and concentric to the periphery of the side plates 66 and67. Within these slots are received the screws 95 for securing the units90 in position. The screws 95 serve as guiding means when the units arerepositioned. Only the developing unit is shown as adjustable. The otherunits 90 may also be made adjustable in the same manner to still furtherregulate the time periods for various processing steps.

The processing solutions are supplied to the unit from a plurality oftanks 96which desirably may be at least partially received within thespace between the side plates 66 and 67. There are four such tanks shownin FIG. 3 and FIG. 8 closely spaced and secured to a supporting platform97. The platform and the tanks extend through the plate 67 to the rightin FIG. 5 a substantial distance beyond the plate. The platform issecured to both plates 66 and 67 by brackets 98 or other suitable means.The elongated contour of the tanks provide a considerable capacity forsolution and each tank is provided with an electric heater 99 projectinginto the liquid within the tanks.

When it is desired to execute a very fast developing operation theheaters maintain the solutions at a temperature elevated above roomtemperature and thus shorten the time cycle for processing prints orother photographic units.

At least one of the tanks is provided with a thermostatic control unit100 connected to a power source and having its controlled outputconnected to the heaters 99. As shown the first tank which is normallyused for developing contains the control unit and has its sensing memberimmersed in the solution. The control 161) may be of conventionalconstruction and has a manual adjustment for selecting the desiredtemperature. This first tank is longer than the others to accommodatethe sensor of the control member.

Desirably the heater in each tank is provided with conventional doublecontact connectors 101.

Controlled power from the member is fed to the heaters 99. Any one orall of the heaters may be rendered active by coupling power to theconnectors 161 through separate power leads 1112. Any suitable means forfeeding power to the heaters may however be used.

Each of the tanks 96 contain a power driven pump 103 immersed in theprocessing liquid and desirably situated close to the bottom of the tankand supported from the tank cover plate 1214. Each tank and pumpassembly is in turn secured to the platform 97. The pumps which may beof the meshed gear type are provided with a vertical drive shaft whichis extended by means of a coupling to project through the cover plateand platform. Desirably the shaft is provided with ball bearingsreceived in the cover plate and platform.

The upper end of each drive shaft has secured thereon a driving gear 166which are interconnected by three idler gears 107 intermeshingtherewith. The idler gears are rotatively mounted on vertical studshafts secured in the platform 97. The center idler gear meshes with andis driven by a gear 168 rotatably mounted upon a shaft 1t fixed to theplatform. The gear 108 has fixed thereto a second gear 111) which mesheswith another gear 111 connected to one of a pair of miter gears 112. Thegear 111 and one of the miter gears are axially coupled and rotate upona stud shaft secured to the platform 97. The other miter gear is securedto the shaft of a motor 113 secured to the platform. Thus all of thepumps are driven by the motor 113.

The solution circulating system of the apparatus is best shown in FIG.10. Each pump is provided with a suction tube 114 and an outlet spout115 which empties into the liquid in the tank desirably below thesolution surface. The suction tubes 114 are extended and coupled to oneof the ports in each of the units 90, as for example, the port 93 ofeach unit. The other ports 92 are connected to liquid conduits 116extending through the top of each tank and down into the solution to apoint close to the bottom of the tank. If desired a check valve 117 maybe inserted in each conduit 116 to prevent draining solution therefromwhen flow therein is stopped.

Operation of the flow system is as follows. The pumps are operatedconstantly during the processing operation.

takes place in the liquid lifting conduits 116. When a print covers theslot @l in any of the units 96 atmospheric pressure is excluded andpressure therein is reduced by the pump causing liquid to be drawn fromthe tank through the conduit 116, laterally through the slot, down thesuction tube 114 and into the pump and is then discharged through thespout 1E5 into the tank. When the print uncovers the slot at atmosphericpressure immediately is restored in the slot and circulation of solutionstops even though the pumps continue to operate. Thus solutions areautomatically applied to the printing sheet as it passes across the slotand such application automatically stops when the print has completedthe travel across the slot.

It should be noted that the successful function of the novel processingsystem of the invention is due in part to the fact that the solutionflow through the slots 91 is motivated from the low pressure side of thepumps 1%. As the print moves through the processing station atmosphericpressure maintains its emulsion face in close contact with theperipheral edges of the slots 91 which provides a seal against leakageof solution and since there is no positive pressure outward at thispoint leakage of solution is practically eliminated.

When the print has traversed all of the processing units 90 it iscompletely processed and is carried by the apron 72 to the drying means'79 which consists of an enclosed chamber 118 one end of which isreceived between the side plates 66 and 67 and its other end extends tothe left to a position where the completed and dried prints aredischarged by the extended portion of the apron 72. Thus the path of theprints doubles back to a position close to their point of entry at theprinting station. This structure greatly reduces the space occupied bythe apparatus.

The bottom wall of the chamber is perforated and spaced a short distancefrom the apron 72. Its right hand end is curved to the contour of theapron. A plurality of electric heaters 119 are positioned at intervalswithin the chamber and connected to a suitable source of current asshown in FIG. 9.

Air under pressure is fed to the chamber and is heated by the heaters119. It then flows through the perforations and upon the prints as theytravel to the discharge point. A conduit 124D connects the dischargefrom the centrifugal blower 4% to the drier 79 thus the blower 49provides a large flow of air under pressure to the drier and through itsconnection 39 also provides vacuum for the chamber 38. A

Power is supplied to the apparatus from source 121 as shown in FIG. 9.Each component may be provided with a suitable control switch not shown.The units 99 may be placed in operation by attaching coupling members122 at the end of cables 102 to the respective double contact connectors101.

The operation of the apparatus is very flexible with respect to thequantity of light flux reaching the unit during exposure and also thetiming of the development steps may be controlled within close limits toproduce the highest possible quality in the finished print or to producespecial effects departing from normal processing procedures.

The light flux may be regulated in various ways. The operating voltageon the lamp 52 may be varied to provide up to 25% variation inintensity. The distance from the lamp to the exposing slot may bevaried. Neutral density filters may be inserted in the path of lightreaching the exposing slot. As pointed out hereinbefore the width oftheexposing slot may be changed by changing the interchangeable plates 55.In addition to this method the 8 slot width may be changed by a suitablemanual adjusting mechanism.

To further adapt the apparatus to various requirements the processingtime cycle is varied by varying the speed of travel of the apron 72which is accomplished by ad justing the speed changing unit 89 until thedesired op-' timum is achieved. This facility provides for the use ofdifferent types of printing emulsions and also for different types andconcentrations of developing and other processingsolutions. A

In the above connection the mechanism for adjusting the slot width maybe mechanically coupled to the speed control means on the speed changingunits 89. This coupling means should be so constructed that the changein slot width would automatically change the processing time to provideoptimum quality in the finished print.

It should be noted in the use of the apparatus that processing timecycles may be held to a certain schedule and compensation in processingrequired by changes in exposure time or other factors may be achieved byadopting the well known two bath developing technique wherein theproportions of the ingredients in each bath may be varied to achieve therequired adaptation to produce optimum results without a correction inprocessing time. Such a processing technique also permits the twoconveying aprons l3 and 72 to operate at the same speed, which is adesirable condition, even though by conventional developing techniquesthe two aprons should operate at different speeds when compensation isrequired to produce optimum results.

Operation of the apparatus with the aprons traveling at different speedsis however a practical procedure. When the apron 72 is traveling fasterthan the apron 18 the bite between the apron 72 and the tires 70, whenthe print to be processed first enters the processing station, issufiiciently firm to overcome the relatively light friction imposed uponthe print at this time by the suction of the chamber 3% holding itagainst the apron 18. Having entered the processing station the print isconveyed therethrough at the speed of the apron 72. The roll 63functions as a directional element in guiding the print at this pointand exerts practically no friction holding back the print when its speedof travel is increased by the apron '72.

Since the same frictional forces are acting when the speed of the apron18 is faster than that of apron '72 there will be slippage of the apron18 upon the print when transfer from one apron to the other takes place.Since the driving friction of apron 18 is light there will be no damageto the print, which is dry at this time, and moreover it will not buckleor wrinkle since at this time the edges of the print are received in theguiding grooves of the members 45.

As explained above the processing units 90 are or may be adjustedperipherally of the discs 66 and 67 to present their slots 91 atdifferent distances along the path of travel of the prints. In thismanner processing times may be varied.

As pointed out above the apparatus of the invention has wide scope inits operation and general utility. In this connection it should bepointed out that contact reproductions may be produced from the smallestnegative or other subject up to the maximum size capacity of theapparatus.

What is claimed is:

1. Photographic proceessing apparatus comprising a conveyor system toreceive and convey an exposed print ing sheet to and through itschemical processing stations, said conveyor including a perforatedconveyor apron of a width substantially that of one of the dimensions ofthe printing sheet, a pair of narrow parallel circular movable edgeguiding and print moving members in line with and engaging the edges anda narrow marginal portion of the printing sheet, said print movingmembers coacting with said conveyor apron to move said printing sheetemulsion side inward in a curved path about the periphery of saidcircular print moving members, a plurality of print processing unitsextending between said print moving members and engaging the emulsionface of the print as it is held between the apron and print movingmembers, a slot like chamber in each of said processing units extendinglaterally substantially the full width of said apron and having theiropen side tangentially engaging the emulsion of the printing sheetacting to apply processing solution to the emulsion side of the printonly as the print moves thereover and vacuum pumping means forcontinuously maintaining a flow of processing solution through saidchamber only when a print is in processing position across and closingthe open side of said chambers.

2. Photographic processing apparatus according to claim 1 and whereinsaid conveyor apron is composed of two in line sections one sectionfeeding printing sheets to the other, power means to drive saidconveyors and independent means to adjust the speed of travel of thesaid apron sections.

3. Photographic processing apparatus comprising a perforated apron typeconveyor system for manipulating a transparency and a printing sheetduring its processing steps, means to continuously drive the conveyor,means for processing the exposed printing sheet consisting of a pair ofaxially alinged fixed circular plates held in parallel Spacedrelationship, the said plates being substantially in line with the edgesof said conveyor apron, narrow large diameter anti-friction bearingshaving inner and outer races mounted on the periphery of said plates,flanged tires of resilient material secured upon the outer race of saidbearings, the flanges thereof being spaced a distance equal to the widthof the printing sheet and substantially the same as the width of saidapron, said apron transversing said tires and holding the marginal edgesof the printing sheet in contact with said tires while the sheet iscarried around said plates emulsion side inward to a discharge point, atleast one processing unitv secured between said plates and having a slotlike chamber therein extending laterally substantially the full width ofthe apron and opening outwardly at a position to'apply a coating ofprocessing solution to the emulsion only of said printing sheets andvacuum pumping and means for maintaining a flow of processing solutionthrough said chamber only when a printing sheet is covering said slot.

4. Photographic processing apparatus according to claim 3 and printdrying means adjacent to the conveyor apron in a position to dry theprint after it has been completely processed.

5. Photographic processing apparatus according to claim 3 and whereinthe means for maintaining flow of processing solution in said slot likechamber comprises a driven pump and a solution reservoir between saidcircular plates, a conduit from the intake of the pump to guiding andorienting said transparency and printing sheet in register one with theother, vacuum means for holding said sheet in contact with said apronfor a portion of its travel after exposure thereof while saidtransparency is separating therefrom, circular marginal edge grippingmeans includinga driven perforated apron coacting with said conveyor totransport said exposed printing sheet with its emulsion side away fromsaid conveyor apron during its chemical processing. steps, a processingsolution reservoir, processing solution applying means consisting of atleast one applicator unit having a slot like chamber with the open sidethereof disposed in the path of the emulsion side of said printing sheetwhereby solution in said chamber is applied only to the emulsion of thesheet, a constantly running pump acting to supply solution to saidapplicator chamber the suction port thereof being connected to one endof said chamber, a conduit connected to the other end of said chamberand extending below the surface of the solution in said reservoir, theexhaust port of said pump discharging into said reservoir whereby when aprinting sheet is covering the open side of said applicator chambersolution flows therethrough and when no printing sheet is present nosolution flows.

7. Photographic processing apparatus according to claim 6 and whereinthe said edge gripping means comprises a pair of narrow large diameteranti-friction bearings having inner and outer races positioned in linewith the margin of said apron, tires of resilient non-corrosive materialsecured to the outer race of said bearings and presenting flat areas andvertical flanges at the outer limit of the flat areas the edges of saidconveyor apron and I said printing sheet being received between saidflanges, the marginal areas of said apron and printing sheet riding uponthe narrow fiat areas of said tires.

8. Photographic processing apparatus according to claim 6 and whereinthe sheet holding vacuum means is positioned to hold and move the sheetuntil it is positively gripped by said marginal edge gripping means.

9. Photographic processing apparatus according to claim 8 and whereinthe said perforated apron has an open flat portion upon which theprocessed print is re ceived upon completion of its processing, a dryingmanifold adjacent said flat portion, a centrifugal type air blower, aconnection from said blower output to said drying manifold and aconnection from the intake of said blower to said sheet holding vacuummeans.

References Cited by the Examiner UNITED STATES PATENTS 2,478,896 8/49Cobb -94 2,492,133 12/49 Cobb 95-94 2,587,350 2/52 Maiwald 95-942,665,619 l/54 Tuttle et al. 95-89 2,747,481 5/56 Normann 95-942,856,829 10/58 Orlando 95-89 2,895,552 7/59 Pomper et al. 214-62,956,494 10/ 60 Tyler et al. 95-94 FOREIGN PATENTS 828,469 2/ 60 GreatBritain.

, 888,350 1/ 62 Great Britain.

NORTON ANSHER, Primary Examiner D. B. LOWE, Examiner,

6. A PHOTOGRAPHIC PROCESSING APPARATUS COMPRISING A CONTINUOUSLY DRIVENPERFORATED APRON CONVEYOR SYSTEM FOR MANIPULATING A TRANSPARENCY AND APRINTING SHEET DURING THE OPERATING STEPS OF THE APPARATUS, EDGE GUIDINGMEANS ASSOCIATED WITH SAID CONVEYOR APRON FOR ACCURATELY GUIDING ANDORIENTING SAID TRANSPARENCY AND PRINTING SHEET IN REGISTER ONE WITH THEOTHER, VACUUM MEANS FOR HOLDING SAID SHEET IN CONTACT WITH SAID APRONFOR A PORTION OF ITS TRAVEL AFTER EXPOSURE THEREOF WHILE SAIDTRANSPARENCY IS SEPARATING THEREFROM, CIRCULAR MARGINAL EDGE GRIPPINGMEANS INCLUDING A DRIVEN PERFORATED APRON COACTING WITH SAID CONVEYOR TOTRANSPORT SAID EXPOSED PRINTING SHEET WITH ITS EMULSION SIDE AWAY FROMSAID CONVEYOR APRON DURING ITS CHEMICAL PROCESSING STEPS, A PROCESSINGSOLUTION RESERVOIR, PROCESSING SOLUTION APPLYING MEANS CONSISTING OF ATLEAST ONE APPLICATOR UNIT HAVING A SLOT LIKE